PHOTO ACTIVATED DISINFECTION ( PAD )

In PAD, a photoactive agent (tolonium chloride,methylene blue , toulidine blue.) is applied to the infected area and left in site for a short period. The agent binds to the cellular membrane of bacteria, which will then rupture when activated by a laser light of appropriate wavelength (e.g. 635-nm radiation emitted by SaveDent; Denfotex Light Systems Ltd,United Kingdom). The light is transmitted into the root canals at the tip of a small flexible optical fiber that is attached to a disposable handpiece. The laser emits a maximum of only 100 mW and does not generate sufficient heat to harm adjacent tissues. Moreover the photo active agent ,( tolonium chloride )is biocompatible and will not stain dental tissue.

                           

                           REF : Hong Kong Dental Journal 2004;1:52-7